Approximately 200,000 patients per year in the U.S. undergo the surgical removal of lumbar disks. Candela Laser Corporation proposes to develop a laser based method for percutaneous decompression of herniated lumbar disks. A pulsed Holmium: YAG laser with a fiber optic delivery system will be used to ablate material and reduce the volume of the nucleus pulposus achieving a clinically important reduction in intradisk pressure. A novel intradisk pressure-volume compliance curve will be generated experimentally to establish the ideal laser parameters which yield the greatest increase in disk compliance. Concomitant studies of thermal effects will be conducted with an infrared thermal camera. In-vitro studies on porcine and human cadaveric lumbar segments will directly compare the laser technique to the nucleotome instrument which represents the currently accepted best technique for removal by the percutaneous route. In-vivo studies on pigs using the established parameters will be conducted to determine any untoward effects. The laser method has the potential advantages of: a minimally invasive technique, a procedure performed on an outpatient basis, greater patient acceptance and a higher clinical success rate. Cost savings of 80% over conventional surgical techniques are anticipated.